Spindle incorporating magnetic coupling for a bobbin



Aug. 25, 1970 R. K. WHITEHEAD, SR, ET 3,525,473

SPINDLE INCORPORATING MAGNETIC COUPLING FOR A BOBBIN Filed Oct. 23, 1968 FIG 2 INVENTORS RICHARD K. WHITEHEAD, SR. RICHARD K. WHIT EHEAD, JR. HARRY C. WHITEHEAD wm Fr.

United States Patent O 3,525,478 SPINDLE IN CORPORATING MAGNETIC COUPLING FOR A BOBBIN Richard K. Whitehead, Sr., Richard K. Whitehead, Jr., and Harry C. Whitehead, Atlanta, Ga., assignors to Springs Mills, Inc., Fort Mill, S.C., a corporation of South Carolina Filed Oct. 23, 1968, Ser. No. 769,916 Int. Cl. B65h 75/30 US. Cl. 242-4621 6 Claims ABSTRACT OF THE DISCLOSURE A spinning frame spindle provided with a magnetic coupling device to prevent creeping up of the bobbin, to aid in driving the bobbin, and to provide uniform release characteristics when the bobbin is doifed. A band of magnetized material and an associated pole piece produce a magnetic circuit which in part passes through the metallic ring at the lower end of the bobbin.

BACKGROUND OF THE INVENTION The drive imparted from a spinning frame spindle to an associated bobbin is effected conventionally by a friction interfit between the tapered bobbin and the bobbinreceiving body portion of the spindle. When this interfit is too tight, difficulties arise in connection with doffing the bobbin, particularly when automatic doffing equipment is utilized, and when the interfit is too loose, the bobbins tend to creep up on the spindle and to be imperfectly driven thereby with the result that the spinning operation is adversely affected.

BRIEF SUMMARY OF THE INVENTION The present invention seeks to overcome the above noted disadvantages by providing a magnetic coupling between a spindle and its associated bobbin wherein the bobbin is held down at substantially uniform pressure sufficient to prevent creeping up of the bobbin on the spindle but allowing of uniformly easy dofiing action. The magnetic couplings also imparts driving motion to the bobbin and its holding action may be utilized to seat the bobbin against a friction driving surface.

The bobbin-receiving body portion of a spinning frame spindle is provided with a collar of non-magnetic material which contains a band of magnetized material, which may be rubber bonded barium ferrite material, magnetized in a direction to provide one magnetic pole at its inner surface and the opposite magnetic pole at its outer surface so as to produce a magnetic circuit which in part passes through the metallic ring at the lower end of the bobbin and serves to seat the lower end of the bobbin positively and uniformly against the collar assembly. To concentrate the lines of flux in the region of the metallic ring of the bobbin, a low carbon steel pole piece encircles the band of magnetized material whereas the inner surface of the band of magnetized material may be placed contiguous to the body of the spindle or an inner ring of low carbon stel may be placed between the spindle body and the band of magnetized material. The pole piece is provided with an inwardly directed upper lip which partly overlies the upper edge of the band of magnetized material and the upper surface of the pole piece may be coated with a layer of nonmagnetic plastic or other cushioning material providing a seat for the metallic ring at the lower end of the bobbin which prevents cutting of the yarn during the doffing operation by pinching betwen the steel bobbin ring and the steel pole piece.

3,525,478 Patented Aug. 25, 1970 Ice BRIEF DESCRIPTION OF THE DRAWING FIGURES DETAILED DESCRIPTION OF THE INVENTION The spindle according to the present invention includes the usual blade portion 10 and whirl 12 and a tapered, generally conical metallic body portion 14 having a base 16 adapted to receive the metallic ring 18 at the lower end of a bobbin 20 in a relatively loose fashion, substantially as is :shown in FIG. 2. A ring-like strip or band 22 of magnetized material (see FIG. 1) is formed into an annulus of approximately the dimensions of the base portion 16 and is enclosed within a sleeve like pole piece 24 of low carbon steel. The pole piece 24 is provided with a radially inturned upper lip 26 whose inner edge 28 is dimensioned to clear and provide space with respect to the outer surface of the base 16, as may be seen in FIG. 2. The magnetized material 22 is magnetized in that direction to provide one magnetic pole at its inner face 30 and the opposite magnetic pole at its outer face 32 to provide a magnetic circuit as is diagrammatically illustrated by the dashed line 34 in FIG. 2 which passes through the magnetized band 22, partly through the pole piece 24, partly through the metallic ring 18 provided at the lower end of the bobbin and partly through the base 16 of the spindle for magnetically seating the bobbin 20 on the spindle to prevent longitudinal movement of the bobbin with respect to the spindle during rotation and which permits easy breaking of the magnetic seating and thereby easy dofiing of the bobbin from the spindle. The result of the assembly as described and shown is to provide a uniform hold-down force between the spindle and the bobbin 20 so that a uniform, predetermined pressure or force is required to lift the bobbin 20 free from the magnetic coupling, thus providing for uniform doffing effort which materially aids not only in manual dofiing but also in automatic doffing as effected by machines constructed for this purpose.

The magnetized band 22 and its pole piece 24 are encapsulated in a collar 38 of nonmetallic material, such as synthetic resinous compositions suitable for this purpose. The band 22 conveniently may be formed of commercially available rubber bonded barium ferrite composite material which accommodates readily to being shaped or flexed into an annular ring fitting snuggly within the pole piece 24. To provide a cushion or buffer between the bobbin ring 18 and the pole piece lip 26 to prevent cutting of the yarn incidental to doffing, and in order to aid in driving the bobbin 20 uniformly with the spinning motion of the spindle 14, the upper surface of the pole piece lip 26 is provided with a layer or coating 40 of synthetic resinous material which also fills the gap between the inner edge 28 of the pole piece lip 26 and the outer surface of the base portion 16 of the spindle assembly. Thus, the hold-down force is also used to drive the bobbin 20. This entirely relieves the necessity for providing a frictional interfit between the spindle and the bobbin since the magnetic coupling not only prevents the bobbin 20 from creeping up the spindle during operation but also holds it down uniformly for a uniform dofiing action and, as well, aids in the spinning drive imparted from the spindle 14 to the bobbin 20.

The modification shown in FIG. 3 will be seen to include a low carbon steel ring 42 encircling the spindle body and fitted snugly within the band 46 of magnetized material which, in turn, is enclosed by the pole piece 44. As before, the pole piece is provided with a lip 48 which partly overlies the upper edge of the magnetized band 46. In both cases shown, the magnetized circuit produced is such as to concentrate the lines of flux in the region at which the magnetic circuit passes through the bobbin ring 18. In FIG. 2, the inner side of the magnetic circuit is principally within the body of the spindle whereas in FIG. 3 it is principally within the steel ring 42.

The present invention, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned as well as others inherent therein. While the presently illustrative embodiments of the invention are given for the purpose of disclosure, numerous changes in the details of construction and arrangement of parts may be made which will readily suggest themselves to those skilled in the art and which are encompassed within the spirit of the invention and the scope of the appended claims.

We claim:

1. A spindle for supporting a bobbin in a predetermined position while imparting rotary motion thereto, said spindle including:

an elongate body having a depending blade, and a portion presenting a base of a diameter for freely receiving a metallic ring at the lower end of a bobbin, a support collar surrounding said body at said base, said collar being formed of non-magnetic material,

an annular band of magnetized material Within said collar and at the upper end thereof, said band being magnetized in a direction to provide one magnetic pole at said inner surface and the opposite magnetic pole at its outer surface, and

a steel member encircling said band so as to form a pole piece and complete a magnetic circuit which passes through the magnetized band, partly through the base of the spindle, partly through the metallic ring of the bobbin and through the pole piece for magnetically seating the bobbin on the spindle to prevent longitudinal movement of the bobbin with respect to the spindle during rotation and which permits easy breaking of the magnetic seating and thereby easy d'offing of the bobbin from the spindle.

2. The spindle according to claim 1 wherein said pole piece is a sleeve surrounding said band of magnetized material and having an inwardly directed lip at its upper end overlying in part the upper edge of said band of magnetized material, the inner edge of said lip being spaced from the surface of said body and the upper surface of said pole piece being disposed substantially at the level of the upper surface of said collar.

3. The spindle according to claim 2 including a layer of synthetic resinous material on the upper surface of said pole piece to provide a seat for a metallic ring at the lower end of the bobbin.

4. The spindle according to claim 1 wherein said pole piece is a sleeve surrounding said band of magnetized material and having an inwardly directed lip at its upper end overlying in part the upper edge of said band of magnetized material, and a steel ring encircling said base and around which said band of magnetized material is snuggly engaged.

5. A bobbin and spindle assembly for textile machines comprising, in combination:

a tapered bobbin having a metallic ring at its lower end,

a spindle having a tapered body portion for guidably but loosely receiving said bobbin, said spindle including a support surface upon which said metallic ring of the bobbin rests, and

a magnetic member below said support surface forming a magnetic circuit passing partly through said metallic ring and partly through said body of the spindle to prevent axial displacement of the bobbin while imparting the spinning motion of said spindle thereto during operation of the spindle.

6. A bobbin and spindle assembly for textile machines comprising, in combination:

a tapered bobbin having a metallic ring at its lower end,

a spindle having a tapered body portion for guidably but loosely receiving said bobbin, said spindle in cluding a support surface upon which said metallic ring of the bobbin rests, and a magnetic member below said support surface forming a magnetic circuit passing partly through said metallic ring and partly through said support surface to prevent axial displacement of the bobbin while imparting the spinning motion of said spindle thereto during operation of the spindle.

References Cited UNITED STATES PATENTS 1,236,965 8/1917 Miller 242-4621 2,561,155 7/1951 Thomas et a1 242-46.2l

FOREIGN PATENTS 945,322 7/ 1956 Germany.

STANLEY N. GILREATH, Primary Examiner US. Cl. X.R. 57--l30 

